Secondary bioreceptivity of granite: effect of salt weathering on subaerial biofilm growth

Salt crystallisation is a very common and powerful weathering agent that can modify the petrophysical properties of building stone such as granite. In addition, the weathering can affect the susceptibility of the stone to biological colonisation. The aims of the present study were to examine the properties of a granite weathered by sodium chloride crystallisation and to evaluate the effects of the weathering on the secondary bioreceptivity of the stone to subaerial phototrophic biofilms. For this purpose, granite samples were subjected to a laboratory-based accelerated salt weathering test, and changes in weight, open porosity, bulk density, capillary water content, abrasion pH and surface roughness of the samples were determined. Samples of both weathered and non-weathered granite were then inoculated with a multi-species phototrophic culture derived from a natural subaerial biofilm and incubated under standardised laboratory conditions for 3 months. The weight loss produced by the weathering process was consistent with significant changes in abrasion pH and surface roughness. The bioreceptivity of the stone was also altered. According to the bioreceptivity index, the granite under study was characterised by ‘mild primary bioreceptivity’, but ‘high secondary bioreceptivity’ after the salt weathering process. Study of the secondary bioreceptivity of stone materials can provide very useful information about response to weathering effects, and the findings can be used to improve the selection of materials for building purposes.     

Measurement of thrombus formation on intravascular catheters

War is a complex social situation due to the interplay of multiple factors. Economical and political ones are of utmost importance, but human attitudes and motivations must be also taken into account. Being desirable to modify human transactions in such a way that they do not interfere with the basic right of everyone to a condition of physical and mental well-being, war must be abolished. The author contends that an understanding of behaviour through Psychology can be helpful in that aim. Aggression is considered the principal psychological cause of war. It is worth while to differentiate between aggression as an instrument for attaining a special end, and as pure hostility. Only in the first form, it is held here, does it play an important role in war. Psychogists must deal also with a wide range of states of mind that can be "served" by aggression: feelings of inferiority or insecurity, fear, greed, projections, compensations, rationalizations, etc. Scientific approach is not the only one Physiology brings to war prevention. It is equally important the wide dissemination of its conclusions among the general public. Information on the dynamics that prompt people to decide war would make it easier to control. This applies not only to political or military leaders, but also to civil populations. Concerning those two possible contributions of psychologists, scientific and educative, it is suggested the extensive use of psychodramatic techniques. Their richness lie in the lifelike experiences they convey to the participants, and particular aptitude to promote changes of attitudes. Investigation and information on the psychological processes related to war should be undertaken by international organizations of social scientists, acting simultaneously in several countries. Some of the initial steps they could further: 1) that prevention of war be a current subject matter in psychological courses; 2) that the World Health Organization take interest in this subject; 3) that psychologists participate in international political and economical bodies in order to clarify the psychological factors leading to war.     

Cardiac syncope due to transient coronary artery occlusion: the role of percutaneous angioplasty

A case of cardiac syncope is presented, associated with single vessel coronary disease. The mechanism of the syncope would appear to be a ventricular arrhythmia with transmural myocardial ischaemia due to transient occlusion of the diseased coronary artery. The symptoms and electrocardiographic abnormalities were reproduced and subsequently abolished by percutaneous coronary angioplasty.     

The effects of deprenyl on methamphetamine-induced dopamine depletions

The effects of deprenyl on methamphetamine-induced dopamine depletions were studied in mice. Four SC injections of 12.5 mg/kg of methamphetamine at two-hour intervals caused substantial (72-82%) and long-lasting depletions of striatal dopamine. Pretreatment with either 25 or 40 mg/kg of deprenyl did not significantly alter the magnitude of this depletion. These results indicate that, unlike what is observed following MPTP, there is no protection afforded dopaminergic cells by deprenyl pretreatment in the methamphetamine model of parkinsonism.     

Incidence risk and aetiology of mammary abnormalities in dry ewes in 10 flocks in southern Greece

In a field investigation of 10 flocks in Southern Greece, 3367 dairy ewes were examined twice, in order to estimate the incidence risk and the aetiology of mammary abnormalities during the dry-period. Abnormal secretion, lumps, nodules, diffuse hardness, abscesses and cysts were the abnormalities detected. The cumulative incidence of mammary abnormalities during the dry-period was 5.1% (95% confidence interval: 4.4-5.8%); 47% of the cases detected developed during the first three weeks after cessation of lactation. Despite variation in the flock size, there was no between-flock variation in the risk of a ewe developing mammary abnormalities. Staphylococci (Staphylococcus aureus and coagulase-negative isolates) were the most frequently isolated bacteria from mammary samples; Actinomyces pyogenes, Clostridium perfringens, streptococci and Escherichia coli were also isolated. Resistance was encountered among the staphylococcal isolates.     

Magnetic resonance images of neuronal migration anomalies

Neuronal migration anomalies are a spectrum of brain malformations caused by insults to migrating neuroblasts during the sixth week to fifth month of gestation. To study the characteristics of MRI findings in migration anomalies, MR images of 36 patients (28 children and 8 adults) with migration anomalies were evaluated. Five patients had lissencephaly, eight had pachygyria, twelve had schizencephaly, six had heterotopias of gray matter, three had hemimegalencephaly, and two had polymicrogyria. The frequency of migration anomalies was 0.51% of all cranial MRI studies and 1.21% of pediatric cranial MRI studies at our hospital. The major clinical presentations of these patients were seizure (64%), development delay (42%), motor deficits (42%) and mental retardation (25%). Twenty-five patients (69%) associated with other brain anomalies, including: other migration anomalies in 12 cases (33%), absence of the septum pellucidum in 10 cases (28%), Dandy-Walker malformation/variant in 5 cases, arachnoid cyst in 4 cases, agenesis of the corpus callosum in 3 cases, holoprosencephaly in 2 cases, mega cisterna magna in 1 case and cephalocele in 1 case. Some of them presented with multiple complicated anomalies. As MR imaging provides superb gray-white matter distinction, details of cortical anatomy and multiplanar capability, it can clearly delineate the detail morphologic changes of the brain caused by neuronal migration disorders as well as the associated anomalies.     

Lupus anticoagulant, anticardiolipin antibodies and hepatitis C virus infection in thalassaemia

Anticardiolipin antibodies (ACA) and lupus anticoagulant (LA) have been detected in patients with hepatitis C virus (HCV) infection and have been associated in autoimmune diseases (i.e. systemic lupus erythematosus) with an increased risk of thromboembolic events. Because of the high prevalence of HCV infection and the thrombotic risk described in thalassaemia we decided to investigate the prevalence of ACA and LA in a cohort of 68 thalassaemia patients. We found a high prevalence (34%) of beta2-glycoprotein I independent ACA in our thalassaemia patients which was related to HCV infection. None of patients developed any complications related to antiphospholipid antibodies (APL); therefore the clinical significance of positivity for APL in patients with HCV infection is at present unclear. In conclusion, the results of our study indicate that ACA in the serum of HCV-infected thalassaemic patients exhibit the characteristics of natural autoantibodies rather than those of the pathogenic autoantibodies that are found in patients with systemic lupus erythematosus.     

Antinociceptive analogs of orphanin FQ/nociceptin(1-11)

The presence of pairs of basic amino acids within the sequence of orphanin FQ/nociceptin (OFQ/N) peptide, the endogenous ligand for the ORL1/KOR-3 receptor, has raised the possibility that processing might generate pharmacologically important truncated peptides, including OFQ/N(1-11). OFQ/N(1-11) is pharmacologically active in vivo with a potency comparable to OFQ/N. Several tyrosine-containing analogs of OFQ/N(1-11) have been synthesized and examined for antinociceptive activity. Like OFQ/N(1-11), [Tyr1]OFQ/N(1-11), [Tyr10]OFQ/N(1-11) and [IodoTyr10]OFQ/N(1-11) given supraspinally in mice were antinociceptive in the tailflick assay in mice. The tyrosine analogs showed similar potencies as OFQ/N(1-11) but longer durations of action. This response was readily reversed by the opioid antagonist naloxone despite poor affinities for these analogs at opioid receptors. Another compound, [Tyr11]OFQ/N(1-11) was highly epileptogenic, inducing naloxone-sensitive seizures in greater than 50% of the mice tested at doses comparable to those examined with the other analogs. These results indicate that it is possible to make analgesic OFQ/N(1-11) analogs. The activity of [IodoTyr10]OFQ/N(1-11) suggests that it may prove useful as a radioligand in exploring potential OFQ/N(1-11) binding sites.